Well, yes. There's Philippine Airlines and Cebu Pacific and others that fly direct from Manila to Sydney.
Then there are several airlines that fly to Auckland and back (Qantas, LATAM, Virgin, Air New Zealand, Jetstar and more).
So for the cheapest ticket, you'll perhaps want to consider booking a return ticket to Sydney, and a return ticket from Sydney to ...
The Immigration NZ web site is clear, as you have discovered: your visa expires when you leave New Zealand.
However, you can return to New Zealand with a visa waiver provided you do not stay more than six months in a twelve month period (Source Enter your details and select Visa Waiver Visitor)
After 1st October 2019 the eTA scheme comes into play. Details ...
I contacted the NZ Transport Agency to ask them if there was any residency requirement for obtaining a driver license. They said anyone can apply for a license while visiting New Zealand.
If they are wanting to apply through the New Zealand Driver Licence
system and are not going to be converting an overseas licence the
The closest law that I can find to banning Somalians from New Zealand is United Nations Sanctions (Somalia) Regulations 2018, which only applies to designated people on a UN list.
No Somali passport is allowed to be endorsed however, which mean you have to get a Certificate of Identity to travel to New Zealand.